1. Field of the Invention
The present invention relates to a hydrogenated ring-opening metathesis polymer having a specific molecular weight distribution, more particularly, a hydrogenated ring-opening metathesis polymer which is excellent in heat resistance, thermal decomposition resistance, light transmittance and the like and easy to be used as a resist film as compared with known polymers and a method of producing the hydrogenated polymer.
2. Description of the Related Art
With the recent increase of integration level in integrated circuits on semiconductor devices, large-scale integrated circuits (LSI) and very-large-scale integrated circuits (VLSI) have been put to practical use and additionally, the minimum lithographic pattern in an integrated circuit would be reaching in submicron feature and in future there is a tendency of further microlithographic. Formation of a microlithographic pattern essentially requires use of a lithographic technology in which a substrate to be treated on which a thin film is formed is coated with a resist material, selective exposure is conducted to form a latent image of a desired pattern, then development is conducted to form a resist pattern which is used as a mask in dry etching, and then the resist material is removed to obtain a desired pattern.
As the exposure light source used in this lithographic technology, ultraviolet lights such as g ray (wavelength: 436 nm) and i ray (wavelength: 365 nm) have been utilized, but with the progress of the fine lithographic pattern, exposure lights having a shorter wavelength such as far ultraviolet ray, vacuum ultraviolet ray, electron beam (EB), X ray and the like have become popular to use as a light source. Particularly recently, excimer lasers (KrF laser having a wavelength of 248 nm, ArF laser having a wavelength of 193 nm) have received attention as an exposure light source and are expected to be effective in formation of a fine lithographic pattern.
As polymers or copolymers used in a resist material forming a sub-micron pattern using exposure light in a region of vacuum ultraviolet ray, cyclic polymers as found in photoresist compositions comprising a polymer compound having a cyclic skeleton which contains an alicyclic hydrocarbon as the main chain and has a pendant acid cleavable group (see Patent Documents 1, 2, 3 and 4) have problems such as poor solubility in a resist solvent at high concentration, poor wettability to a developer, poor adhesion to a silicon substrate and the like, though these cyclic polymers are excellent in dry etching resistance and excellent in transparency to far ultraviolet ray.
To resolve such problems, the present inventors previously suggested a polymer having a narrow molecular weight distribution which was prepared by subjecting a specific cyclic olefin to living metathesis polymerization followed by hydrogenation (see Patent Document 5).                [Patent Document 1] WO97/33198        [Patent Document 2] JP-A No. 09-230595        [Patent Document 3] JP-A No. 09-244247        [Patent Document 4] JP-A No. 10-254139        [Patent Document 5] WO01/79324        